Ever new materials came on the market, for example the thin Mylar foil that makes space suits heat resistant. It is used, among other things, as a membrane in loudspeakers and for aroma-proof packaging of food products. Tinsel and helium balloons are also made of Mylar foil. For its part, polyvinyl chloride (PVC) made it possible to devise airy constructions and architectures with futuristic dimensions destined to foster a feeling of freedom and lightness.